Parallel major and minor keys share the same root but have different notes: C major is C, D, E, F, G, A, B, while C minor is C, D, Eb, F, G, Ab, Bb. The minor key lowers the 3rd, 6th and 7th degrees by a semitone, which changes the key signature from none to three flats.
What are parallel major and minor keys?
Parallel major and minor keys share the same root but have different notes. C major is C, D, E, F, G, A, B, while C minor is C, D, Eb, F, G, Ab, Bb, spelled C, D, D#, F, G, G#, A# in the sharp-only system used by ChordFlow. The minor key lowers the 3rd, 6th and 7th degrees by a semitone, which changes the key signature from no sharps or flats to three flats, and it changes the sound from bright to dark, even though the home note stays the same. Parallel keys matter because moving between them is one of the most dramatic changes in music. A song that moves from C major to C minor does not change its home note, but it changes its whole character, from bright to dark, and the listener hears the shift immediately. That is why parallel modulation is used at emotional turning points in music, such as the move from a major verse to a minor chorus, or the Picardy third, where a minor piece ends on a major chord, which is the opposite move: the tonic chord changes from minor to major, and the ending sounds like a sunrise after a storm. The key of C major and the key of C minor show the pair.
How parallel keys work
To find the parallel minor of a major key, lower the 3rd, 6th and 7th degrees by a semitone. C major is C, D, E, F, G, A, B, so C minor is C, D, Eb, F, G, Ab, Bb: the E drops to Eb, the A drops to Ab, and the B drops to Bb. To find the parallel major of a minor key, raise the 3rd, 6th and 7th degrees by a semitone. A minor is A, B, C, D, E, F, G, so A major is A, B, C#, D, E, F#, G#: the C rises to C#, the F rises to F#, and the G rises to G#. The key signatures differ by three sharps or flats: C major has none and C minor has three flats, while A minor has none and A major has three sharps. The parallel keys share the root and the 5th, which are the most stable notes of the scale, and they differ in the 3rd, 6th and 7th, which are the notes that give the scale its character. That is why a parallel modulation sounds both familiar and strange: the home note is the same, but the colour has changed. The chords differ too: C major has C, Dm, Em, F, G, Am and Bdim, while C minor has Cm, Ddim, Eb, Fm, Gm, Ab and Bb, so only two chords, F and G, are shared in their major form, and the rest change quality. The key of G major and the key of G minor show another parallel pair.
Worked example — G major vs G minor. G major is G, A, B, C, D, E, F#, with one sharp, and its chords are G, Am, Bm, C, D, Em and F#dim. G minor is G, A, Bb, C, D, Eb, F, with two flats, and its chords are Gm, Adim, Bb, Cm, Dm, Eb and F. The 3rd drops from B to Bb, the 6th drops from E to Eb, and the 7th drops from F# to F, each by one semitone, and the key signature changes from one sharp to two flats. Play the I–V–vi–IV progression in G major, G, D, Em, C, and then play the i–VI–III–VII progression in G minor, Gm, Eb, Bb, F, and listen for the same home note sounding major in one place and minor in the other.
How to practise parallel keys
Practise parallel keys as pairs, major then minor, so your ear learns to hear the same home note with two different colours.
- Play the C major scale and then the C minor scale, and listen for the 3rd, 6th and 7th dropping by a semitone.
- Play the chords of the key of C major in order, then the chords of the key of C minor, and count how many chords change quality.
- Find the parallel minor of G, D, A and E major, and check that each pair differs by three sharps or flats in the key signature.
- Play a major chord and then the minor chord on the same root, back to back, and listen for the single note that changes the mood.
- Use the relative major minor finder to find the relative of each parallel key, and check that the relative minors differ too.
Common mistakes
- Confusing parallel and relative keys — Parallel keys share the same root and have different notes, while relative keys share the same notes and start on different roots. C major and C minor are parallel; C major and A minor are relative, and confusing the two leads to wrong chord choices.
- Thinking parallel keys share a key signature — Parallel keys have different key signatures, differing by three sharps or flats, because their notes differ. C major has no sharps or flats and C minor has three flats, so the signatures are not the same.
- Forgetting the harmonic minor scale — The parallel minor key uses the harmonic minor scale for its V chord, making it major, just as any minor key does. If you play a minor v chord in a parallel minor key, the cadence will sound weak.
Quick reference
This table lists six pairs of parallel major and minor keys, with the notes that are lowered and the change in the key signature, so you can see the relationship working across the sharp keys and the flat keys. In every row the 3rd, 6th and 7th degrees drop by a semitone, and the key signature changes by three sharps or flats.
| Major key | Parallel minor | Notes lowered | Key signature change |
|---|---|---|---|
| C major | C minor | E to Eb, A to Ab, B to Bb | None to 3 flats |
| G major | G minor | B to Bb, E to Eb, F# to F | 1 sharp to 2 flats |
| D major | D minor | F# to F, B to Bb, C# to C | 2 sharps to 1 flat |
| A major | A minor | C# to C, F# to F, G# to G | 3 sharps to none |
| E major | E minor | G# to G, C# to C, D# to D | 4 sharps to 1 sharp |
| F major | F minor | A to Ab, D to Db, E to Eb | 1 flat to 4 flats |
Work through the table by playing each pair on your instrument, major first and then minor, and listening for the same home note sounding bright and then dark. When you can hear the difference, try the exercise in reverse: start from a minor key and raise the 3rd, 6th and 7th degrees to find its parallel major.
Frequently asked questions
What are parallel major and minor keys?
Parallel major and minor keys share the same root but have different notes: C major is C, D, E, F, G, A, B, while C minor is C, D, Eb, F, G, Ab, Bb. The minor key lowers the 3rd, 6th and 7th degrees by a semitone.
How do I find the parallel minor of a major key?
Lower the 3rd, 6th and 7th degrees by a semitone. C major is C, D, E, F, G, A, B, so C minor is C, D, Eb, F, G, Ab, Bb, and the key signature changes from none to three flats.
What is the difference between parallel and relative keys?
Parallel keys share the same root and have different notes, while relative keys share the same notes and start on different roots. C major and C minor are parallel; C major and A minor are relative.
Do parallel keys share chords?
Some, but not all. C major and C minor share the F and G chords in their major form, but the other chords change quality, because the notes differ. The tonic chord changes from major to minor, which is the most important difference.
What is a Picardy third?
A Picardy third is a major tonic chord at the end of a minor piece, where the listener expects a minor chord. The 3rd of the final chord is raised from minor to major, so the piece ends in the parallel major, and the ending sounds bright and hopeful after the darkness of the minor key.